Combined drafting and measuring tool.



Patented Dec. 25, I900.

W. C. DAY.

COMBINED DRAFTING .AND MEASURING TOOL {Application filed Mar. 22, 1900.)

(No Model.)

INVENTDR Zz1wr WITNEEEEEJ We nouns versus cu, PHOTO-LITNO, wnsnmomw, '1 c.

UNITED STATES PATENT OFFICE.

WILLIAM C. DAY, OF RUMFORD FALLS, MAINE, ASSIGNOR TO THE NATIONAL DRAFTING TOOL COMPANY, OF LIVERMORE FALLS, MAINE.

COMBINED DRAFTING AND MEASURING TOOL.

SPECIFICATION forming part of Letters Patent No. ,7 7. dated December 255 Application fil'ed March 22, 1900. Serial No. 9676- (N model- To all whom it may concern..- I inner end of the set-screw may be ciit away;

Be it known that I, WILLIAM 0. DAY, of so that said set screw may bear directly Rumford Falls, in the county of Oxford and against the extension 11. In the present case State ofMaine,haveinvented certain newand the extensions are pointed to serve as di- 55 useful Improvements in a Combined Draftvider-legs. One of these may be adapted to ing and Measuring Tool, of which the followhold a pencil. The legs ct a are formed at ing is a specification. their upper ends with ears a a which bear This invention relates to dividers or comon opposite sides of a central pivot-block 17, passes, calipers, and similardrafting or meashaving trunnions b b, on which the ears are 60 IO uring tools in which the legs are connected fitted to turn. The ears are held on the trunby equalizing devices and in which means nions by screws 0 c, entering tapped orifices are provided for permitting either a quick ad in the trunnions, and washers c 0', held by the justment of the legs or a fine and slow adheads of the screws against the outer faces justment of the legs in tools of this charof the ears. 5

I5 acter. On the inner sides of the arms at a are The invention consists in certain features formed recesses a 0, in which are pivoted of improvement in structure and arrangeon pins e c the upper ends of two links 6 e ment, which I shall now proceed to describe of equal length. The lower ends of said links and claim. are pivoted on pins 6 6 between ears formed 70 Of the accompanying drawings, forming a on a collar f. Said collar slides on the lower part of this specification, Figure 1 represents end of a rod d, depending centrally between a side elevation of a tool constructed in acthe legs a, a from the pivot-block b. A stud cordance with my invention and arranged to f' passes through the collar fand has an oribe used as dividers. Fig. 2 represents a verficef Fig. 7, through which the rod (1 passes. 75'

tical sectional view. Fig. 3 represents asec- Said stud is screwthreaded to engage a tion on line 3 3, Fig. 1, on an enlarged scale. clamping-nut), which bears against one side Fig. 4 represents in separate views the upof the collar. When the nut is tightened, per ends of the legs detached. Fig. 5 reprethe stud f exerts lateral pressure against the sents in separate views the pivot-block and rod 61, holding it from sliding in the collar. 80.

o adjusting device, detached. Fig. 6 repre- The spreading apart of the legs a a, acting sents a section on line 6 6 of Fig. 1. on the collar fthrough the links 6 6, moves The same reference characters indicate the said collar upward on the rod (1 in the direcsame parts in all the figures. tion of the pivot-block I), while the closing of In the drawings, a a are the legs of the inthe legs toward each other produces a reverse 85 strument, each of which is preferably of anmovement of the collar along the rod. By

gular form, as shown in Fig. 1. The lower screwing the set-nutf tight against the colportion of each leg I have represented by lar f, and thereby clamping the collar fto dotted lines as socketed and provided with the rod d, the legs a ct are held immovable at a collar 0, havinga set-screw a, whereby exthe distance apart to which they have been 90 4o tensions 't' 't' of different form may be secured moved, except when further adjusted by the to the legs and readily removed, the form of longitudinal movement of the rod caused by the extension depending upon the use to theimeans which I shall now describe. which it is desired to put the instrument. 2') represents a tubular socket formed on Either of the extensionst' can be fastened in the pivot-block b and projecting upwardly 5 its respective socket by the pressure of the therefrom. In said socket is fitted to rotate end of the set-screw a against the outside an internally-tapped sleeve or adjusting-nut wall of the socket, pressing or bending the b which has. a milled head I), by which it latter inward suiiicient to obtain the necesmay be rotated. The upper portion of the sary friction between the said extension and rod cl is threaded to engage the internal I00 the inner surface of the socket. Obviously, thread of the sleeve or nut b the rod being however, the wall of the socket opposite the fitted to slide in an orifice extending through the pivot-block b. When the nut b is 1'0- tated, the rod d is raised or lowered, as the case may be, and a slow movement is imparted from it to the legs at a through the collar fand links e e, the legs moving simultaneously in opposite directions. Endwise movement of the nut 19 is prevented by a segmental wire key or pin 19 which is inserted through a slot b, Fig. 1, formed in one side of the socket b and enters coinciding grooves in the inner surface of the socket and the external surface of the adjusting-nut. A spring j is interposed between the bottom of the socket b and the lower end of the adjustingnut, said spring exerting upward pressure on the nut and on the rod 61 and taking up any lost motion that may exist in consequence of looseness in the various joints'and connections and preventing any loos'eness of the legs a a.

It will be seen that the socketb projecting above the pivot-block, constitutes not only aholder for the adjusting-nut, but also in connection with the head b of said nut-a handle by which the instru'ment'i'nay be conveniently manipulated.

In the operation of the instrument the legs a a may be brought to theirappr'oxima'te adjustment quickly by loosening the nut f and moving said legs apart or together, as require'd', and then having tightened said setscrew the adjusting-nut '5 may be worked to bring the legs a a to an exact or minute adjn stinent.

The particular shape or office of the instrument-legs is immaterial to my invention.

1. An instrument of the character described, comprising a pivot-block having a socket'e'd projection, a pair of legs jointed to said block, an adjusting-nut rotatable in the pivot-block,a rod extendingth rough the pivotbl'o'ck and adapted "to slide therein, the upper portion of the'ro'd having ascrew-thre'a'd connection with th'e'adjusting-nut, a pair of links pivoted to the legs, a sleeve pivoted to the links and having means for detachable connection with the rod, and a spring interposed between the socket and the adj ustingnut.

socketed projection, a pairof legs jointed to said block, an adjusting-nut 'rotatablein the pivot-block, a rod extending through the pivot-block and adapted to slide therein, the upper portion of the rod having a screwthread connection with the adj usting-nut, a pair-of links pivoted to the'legs, a sleeve pivoted to the links, a transverse threaded stud movable in the sleeve and formed to bear on the rod within the sleeve, and a clamping-nut engaged *with the stud and bearing against the sleeve.

3. An instrument of the character speci- 'fied, comprising a pivotb'lo'ck, pair of legs jointed't'o the block, a rod movable in the pivot-block and projecting below the same, means carried by the pivot-'bleck 'foradjustingthe'rodleng-thwise, a pairof links'p'ivoted to thelegs, a sleeve'pivo'ted 't'o'the links, a transversestud movable in the sleeve and formed to bear on the rod 'withi'nfthesl'eeve,

and a clamping-nut engaged with the stud and'bearing against the sleeve.

4. An instrument of "the character "specified, comprising a pivot-block having trunnio'ns, a pair of legs'fitted to swing on said instrument of the character de-' scribed, comprising a pivot-block having .a 

